[R] reading in all files of a certain type

[Dan Davison]

Dimitri Liakhovitski <dimitri.liakhovitski at gmail.com> writes:

> Thanks again - and one follow-up question.
> When I do do.call(rbind, lapply(dir(patt = "\\.csv$"), read.csv))
> What is the right way to speicify (probably under "patt") that I only
> need to grab those .csv files that contain a certain string, e.g.,
> "result"?

I assume you mean whose names contain a certain string, rather than the
string being in the file contents.

The "pattern" argument to dir() is a "regular expression". They are a
worthwhile thing to know a bit about, so, you should have a look at some
introductory material on regular expressions, but this might also help a
bit:

> dir()
[1] "1-result.csv" "result-2.csv" "resultcsv"    "result.csv"  
> dir(patt="result\\.csv$")
[1] "1-result.csv" "result.csv"  
> dir(patt="result.*\\.csv$")
[1] "1-result.csv" "result-2.csv" "result.csv"  

Dan


> I tried a couple of things, like patt= "\\.csv$" & pat = "result" -
> but it does not seem to work
> Thanks a lot!
> Dimitri
>
>
>
> On Wed, May 12, 2010 at 6:16 PM, Dimitri Liakhovitski
> <dimitri.liakhovitski at gmail.com> wrote:
>> Thanks a lot, Henrique, will try!
>> Dimitri
>>
>> On Wed, May 12, 2010 at 3:41 PM, Henrique Dallazuanna <wwwhsd at gmail.com> wrote:
>>> Try this:
>>>
>>> do.call(rbind, lapply(dir(patt = "\\.csv$"), read.csv))
>>>
>>> On Wed, May 12, 2010 at 4:32 PM, Dimitri Liakhovitski
>>> <dimitri.liakhovitski at gmail.com> wrote:
>>>>
>>>> Hello,
>>>>
>>>> I am wondering if it's possible to read in all files of a certain type
>>>> - without specifying their names.
>>>> For example, I have 10 .csv files in my working directory.
>>>> I would like to read them in and bind them all together. I was
>>>> thinking of writing a loop, read in all files, and then bind them.
>>>> Is it possible?
>>>>
>>>> Thanks a lot!
>>>>
>>>> --
>>>> Dimitri Liakhovitski
>>>> Ninah Consulting
>>>> www.ninah.com
>>>>
>>>> ______________________________________________
>>>> R-help at r-project.org mailing list
>>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>>> PLEASE do read the posting guide
>>>> http://www.R-project.org/posting-guide.html
>>>> and provide commented, minimal, self-contained, reproducible code.
>>>
>>>
>>>
>>> --
>>> Henrique Dallazuanna
>>> Curitiba-Paraná-Brasil
>>> 25° 25' 40" S 49° 16' 22" O
>>>
>>
>>
>>
>> --
>> Dimitri Liakhovitski
>> Ninah Consulting
>> www.ninah.com
>>